Prophy angle and adapter

ABSTRACT

A dental prophy angle includes a housing and a rotor. The dental prophy angle adapter can include a drive shaft with a tip. The drive shaft of the adapter can be coupled to a gear at the same end of the tip with the rotor of the prophy angle being configured to receive the tip. Further, a slidable sleeve can extend over a portion of the drift shaft so that the slidable sleeve becomes automatically retracted upon engaging a shoulder of the housing resulting in the gear of the drive shaft being revealed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.11/862,628, filed on Sep. 27, 2007, now U.S. Pat. No. 8,123,523, whichis a Continuation-In-Part of U.S. application Ser. No. 11/189,193, filedon Jul. 26, 2005, now U.S. Pat. No. 7,422,433, and aContinuation-In-Part of U.S. application Ser. No. 11/682,927 filed onMar. 7, 2007, now abandoned, all of which are incorporated herein byreference in their entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The disclosure relates generally to dental instruments and, morespecifically, to prophy angles and adapters for use with prophy angles.

2. Description of the Related Art

Dental prophylaxis angles, generally referred to as “prophy angles,” arecommonly used dental instruments for providing rotation for dental toolssuch as brushes, prophy cups, or other receptacles used incleaning/polishing teeth. Referring to FIGS. 1A and 1B, a prophy angle10 can include an inner housing 16 having an outer housing 18 and arotor 14 extending at approximately a 90° angle to the neck 18, whichincreases the ability of a dentist to reach various surfaces of theteeth of a patient. A drive shaft or rotating member 12 can be locatedwithin the housing 16 and attached to a driven gear 20 in the head ofthe prophy angle. Prophy angles 10 are generally affixed to an adapteror hand piece (not shown), which connects the prophy angle to a drivesource (not shown), thereby enabling a rotating motion of the rotatingmember 12 and driven gear 20 of the prophy angle and any affixed dentaltool.

Prophy angles 10 are commonly manufactured from lightweight plastic tomake them disposable, thereby increasing overall sterility in the dentalenvironment. Being disposable, there is a desire to reduce the costand/or complexity of assembly of the prophy angle 10 while, at the sametime, maintaining the functionality and safety of the prophy angle 10.

One technique to reduce cost is to limit the number of separate piecesin the assembly of the prophy angle 10. For example, the prophy angle inFIG. 1B includes four separate pieces: (i) the rotating member 12, (ii)the inner housing 16, (iii) the outer housing 18, (iv) and the rotor 14.A reduced number of separate pieces requires less molds to form theseparate pieces and less assembly of the pieces. However, by reducingthe numbers of separate pieces, each individual and separate piecetypically becomes more complex as each piece can take on more functions.

One of the issues preventing further reduction in the number of piecesin a disposable prophy angle 10 relates to the ability of the prophyangle 10 to maintain and restrain the position of the rotor 14 withinthe outer housing 16. Since the rotor 14 both engages the rotatingmember 12 and rotates at a head speed, the position of the rotor 14within the outer housing 16 is critical to maintain a proper engagementbetween the rotating member and the rotor 14 and to prevent the rotor 14from being unbalanced during rotation. An improperly positioned and/orrestrained rotor 14 can cause failure of the prophy angle 10 and/orcauses damage to the adaptor, the dental professional and/or thepatient. There is, therefore, a need for an improved prophy angle thatreduces the number of pieces in the prophy angle yet while maintainingthe positional stability of the rotor within the outer housing.

BRIEF SUMMARY OF THE INVENTION

Embodiments of the invention provide a novel and non-obvious dentalprophy angle. The dental prophy angle includes a housing and a rotor.The housing defines a first bore and a second bore in communication withthe first bore, and rotor is disposed within the second bore. The rotorincludes a gearing system, and rotor includes a lock having a lockchannel configured to receive a tip of a drive shaft. The housingincludes a lock receiver for receiving the lock, and the lock receiverpermits rotation of the lock within the lock receiver and restrainslinear movement of the lock in a direction substantially parallel to arotational axis of the rotor. The lock includes a upper portion and alower portion, and the upper portion and the lower portion define thechannel. A seal is positioned between the housing and the rotor, and thesecond bore is adapted to removably receive the drive shaft.

In another embodiment of the invention, a dental adapter for a prophyangle includes a nose, a body connected to the nose, a drive shaftextending from the nose, and a slidable sleeve extending over at least aportion of the drive shaft. The drive shaft includes a gear. In aretracted position of the slidable sleeve, the gear is revealed, and inan extended position of the slidable sleeve, the slidable sleeve atleast partially covers the gear. The drive shaft is linear movablerelative to the body along a line substantially parallel to alongitudinal axis of the drive shaft. A resilient member is connected tothe drive shaft for biasing the drive shaft along the line. The driveshaft includes a tip extending from a distal end of the drive shaft, andthe tip is adapted to engage a rotor of the prophy angle. The adapterincludes a drive source connected to the drive shaft by a coupler.

In yet another embodiment of the invention, a dental tool includes aprophy angle and an adapter for receiving and driving the prophy angle.The prophy angle includes a housing and a rotor, and the adapterincludes a body, a drive shaft for driving the rotor, a slidable sleeve,and a nose for receiving the prophy angle. The rotor includes a lockhaving a lock channel configured to receive a tip of a drive shaft. Theengagement of the lock channel and the tip restrains movement of therotor lock in a direction towards the drive shaft and restrains movementof the lock relative to the tip in a direction substantially parallel toa rotational axis of the rotor. In a retracted position of the slidablesleeve, a gear of the drive shaft is revealed, and in an extendedposition of the slidable sleeve, the slidable sleeve at least partiallycovers the gear. The rotor includes a rotor conduit having an inlet andan outlet, the housing includes a housing conduit having an inlet and anoutlet, and the adapter includes a supply conduit having an outlet. Theoutlet of the housing conduit is connected to the inlet of the rotorconduit, and the outlet of the supply conduit is releaseably connectedto the inlet of the housing conduit.

Additional aspects of the invention will be set forth in part in thedescription which follows, and in part will be obvious from thedescription, or may be learned by practice of the invention. The aspectsof the invention will be realized and attained by means of the elementsand combinations particularly pointed out in the appended claims. It isto be understood that both the foregoing general description and thefollowing detailed description are exemplary and explanatory only andare not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute partof this specification, illustrate embodiments of the invention andtogether with the description, serve to explain the principles of theinvention. The embodiments illustrated herein are presently preferred,it being understood, however, that the invention is not limited to theprecise arrangements and instrumentalities shown, wherein:

FIGS. 1A and 1B are, respectively, a perspective view and a sidecross-sectional view of a prophy angle;

FIGS. 2A and 2B are, respectively, side and cross-sectional side viewsof the rotor;

FIG. 3 is a cross-sectional side view of a drive shaft engaging therotor, in accordance with the inventive arrangements;

FIGS. 4A, 4B, and 4C are, respectively, cross-sectional side, rear, andtop views of the housing;

FIGS. 5A and 5B are, respectively, exploded and assembledcross-sectional side views of a housing and a rotor in accordance withthe inventive arrangements;

FIGS. 6A and 6B are, respectively, exploded and assembledcross-sectional views of a prophy angle and adapter in accordance withthe inventive arrangements;

FIGS. 7A and 7B are cross-sectional side views of the adapter with asleeve, respectively, in extended and retracted positions, in accordancewith the inventive arrangements; and

FIG. 8 is a cross-sectional side view of a portion of the adapter andthe drive shaft.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIGS. 5A-5B and 6A-6B, a prophy angle 100 and adaptor 400are disclosed. The prophy angle 100 includes a rotor 200 positionedwithin a housing 110. The prophy angle 100 is adapted to fit over adrive shaft 350 and engage the adaptor 400, and in certain aspects, thedrive shaft 350 is part of the adaptor 400. In operation, the prophyangle 100 may be inserted onto and removed from the adaptor 400 so as tobe considered disposable.

Referring to FIGS. 2A and 2B, the rotor 200 includes an attachmentdevice 210 to which an attachment, such as a prophy cup (not shown), canbe attached. Many types of attachment devices 210 are known as capableof connecting an attachment to a rotor 200, and the rotor 200 is notlimited as to a particular type of attachment device 210 so capable. Forexample, the attachment device 210 may be a button. Although the buttonis not limited as to a specific shape or orientation, the button 210 mayinclude additional protrusions 215 to accommodate a specific prophy cup.Another example of an attachment device 210 is a prophy cup with athreaded post molded inside.

The rotor 200 may include a radially-extending flange 220. In certainaspects of the rotor 200, the radially-extending flange 220 is sized toextend beyond an opening within the housing 110 (see FIG. 5B). Theflange 220 of the rotor 200 may also be positioned over the opening tothe second bore 114. In so doing, the flange 220 reduces the incidenceof debris from the prophy cup or other attachment from entering theinterior of the housing 110, which could potentially interfere with thesubsequent operation of the prophy angle 100.

The rotor 200, while positioned within the second bore 114 (see FIGS. 5Aand 5B), creates a seal 280 between the rotor 200 and an inner surface134 of the second bore 114. Creating a seal between two surfaces is wellknown in the art, and any manner of creating a seal is acceptable foruse with the prophy angle 100. However, in certain aspects of the prophyangle 100, one of the rotor 200 and the inner surface 134 of the secondbore 114 includes an annular extension 282 and the other of the rotor200 and the inner surface 134 includes an annular groove 182. Upon therotor 200 being positioned within the second bore 114, the rotor 200and/or the housing 110 deforms so as to permit the annular extension 282to be inserted into the annular groove 182 and create the seal 280. Theseal 280 also acts to restrain linear movement of the rotor 200 relativeto the housing 110. Although not limited in this manner, upon theassembly of the rotor 200 with the housing 110, a lubricant may be addedto ease the positioning of the rotor 200 within the housing 110 and/orreduce friction upon the rotor 200 rotating within the housing 110during operation.

The rotor 200 includes a gearing system 230 to drive the rotation of therotor 200 within the housing 110. Many types of gearing systems 230 areknown capable of driving the rotation of the rotor 200 within thehousing 110, and the rotor 200 is not limited as to a particular type ofgearing system 230 so capable. However, in certain aspects of the rotor200, the gearing system 230 includes one gear of a bevel gear set. Aswill be described in more detail below, the other gear 352 of the bevelgear set is attached to the drive shaft 350 (see FIG. 3) and ispositionable within the housing 110.

The rotor 200 also includes a lock 240. The lock 240 interacts with alock receiver 120 (see FIGS. 4A-4C) of the housing 110 to restrainlinear movement of the rotor 200 within the housing 110 yet allowrotation of the rotor 200 within the housing 110. In particular, thelock receiver 120 can restrain linear movement in a directionsubstantially parallel to a rotational axis of the rotor 200. In certainaspects of the lock 240, the lock 240 has a partially-curved outerprofile 242. Also, portions of the lock 240 may have a substantiallyspherical profile 242 taken along a cross-section perpendicular to alongitudinal axis of the rotor 200. In so doing, the lock 240 interactswith the lock receiver 120 of the housing 110 to allow rotation of therotor 200 within the housing 110.

The rotor 200 may also include a rotor conduit 260 having an inlet 265and an outlet 270, and the prophy angle 100 is not limited as to theparticular use of the rotor conduit 260. For example, the rotor conduit260 may be used to transfer materials (e.g., dentifrice, water) to aworking area of the prophy angle 100. Alternatively, the rotor conduit260 may be used as part of a system to provide suction to the workingarea of the prophy angle 100.

Referring to FIG. 3, in certain aspects of the rotor 200, the lock 240includes a recessed lock channel 250 for receiving a tip 355 extendingfrom a distal end of a drive shaft 350. Upon the drive shaft 350 beingengaged within the lock 240, the tip 355 is positioned within the lockchannel 250. While so positioned, engagement between the tip 355 andupper and lower portions 255U, 255L of the lock 240 can restrictmovement of the lock 240, respectively, in a downward direction and anupward direction. Moreover, a width of the lock channel 250 between theupper and lower portions 255,U 255L can be dimensioned slightly greaterthan a diameter of the tip 355 to further restrict movement of the lock240 relative to the tip 355 and vice versa.

Although the lock 240 is illustrated as having both an upper portion255U and a lower portion 255L, the lock 240 is not limited in thismanner. For example, the lock 240 may only include the lower portion250L, which would restrain movement of the lock 240 in the upwarddirection. The drive shaft 350 also restricts movement of the lock 240in a direction towards the drive shaft 350.

In certain aspects of the rotor 200, however, the lock 240 includes bothan upper portion 255U and a lower portion 255L. These two portions 255U,255L, acting together, can restrain rotation of the drive shaft 350about a specified axis of rotation and position the draft shaft 350within the specified axis of rotation. The drive shaft 350 typicallyrotates at a high speed, and any imbalance of the drive shaft 350 cancause the drive shaft 350 to wobble during rotation, which can damagethe drive shaft 350 and/or prophy angle 100 and/or cause poor engagementbetween the drive shaft 350 and the gearing system 230. However, byconstraining the distal end (i.e., the tip 355) of the drive shaft 350with the upper and lower portions 255U, 255L of the lock 240, thiswobble, if present, can be reduced.

A further discussion of engagement of the rotor 200 and the drive shaft350 and between the rotor and the housing 110 and the configurationsthereof is found in related U.S. application Ser. No. 11/189,193, filedon Jul. 26, 2005, incorporated herein by reference in its entirety.

Referring to FIGS. 4A-4C and 5A-5B, the housing 110 is illustrated. Thehousing 110 includes a first bore 112 and a second bore 114. The firstbore 112 extends along a longitudinal length of the of housing 110 andis configured to receive the drive shaft 350 (see FIG. 6B). The secondbore 114 communicates with and extends substantially perpendicular fromthe first bore 112. The second bore 114 is also configured to receivethe rotor 200. Although not limited in this manner, the housing 110 canbe constructed from a variety of available plastics having sufficientrigidity to apply pressure to a patient's teeth, while remainingflexible enough to receive the internal components of the prophy angle.

The first bore 112 may also be configured to receive the adapter 400(see FIG. 6B). Although not limited in this manner, the inner surface116 of the first bore 112 may define a first shoulder 118 that limitsmovement of a portion of the adapter 400 past the shoulder 118. Theadapter 400 engaging the first shoulder 118 may also be used tospecifically position the adapter 400 and, thus, the drive shaft 350,within the housing 110. Other features capable of specificallypositioning the adapter 400 within the housing 110 are known and can beused with the present adapter 400 and housing 110.

Positioned within the second bore 114 is a lock receiver 120. The lockreceiver 120 receives the lock 240 of the rotor 200 and acts to restrainlinear movement of the rotor 200 within the housing 110 yet allowrotation of the rotor 200 within the housing 110. In certain aspects,the lock receiver 120 includes a plurality of bearing arms 122positioned within the second bore 114. The bearing arms 122 may includean upper bearing surface 124 and also a recess 126 on a radiallyinward-facing surface of the bearing arm 122. The recess 126 may have aprofile configured to receive the lock 240 of the rotor 200.

The housing 110 may also include a housing conduit 128 having an outlet130 that releaseably connects with the inlet 265 of the rotor conduit260. The housing conduit 128 also includes an inlet 132 that isconfigured to be releaseably connected to the adapter 400.

Referring specifically to FIGS. 5A and 5B, the prophy angle 100 isassembled by inserting the rotor 200 into the second bore 114. Upon therotor 200 being positioned within the second bore 114 of the housing110, the lock 140 of the rotor 200 is nested within the lock receiver120 of the housing 110. As previously described, upon the lock 140 beingnested within the lock receiver 120, movement of the rotor 200 out ofthe second bore 114 is restrained. Also, upon insertion of the rotor 200within the second bore 114, the seal 280 between the rotor 200 and theinner surface 134 of the second bore 114 engages, which can furtherrestrain movement of the rotor 200 out of the second bore 114. Byrestraining movement of the rotor 200 out of the second bore 114, a usercan handle/manipulate the prophy angle 100 with reduced fear that theprophy angle 100 will become unintentionally disassembled.

Referring to FIGS. 6A and 6B, the prophy angle 100 is shown beingassembled with an adapter 400, and FIGS. 7A and 7B illustrate theadaptor 400. The adapter 400, directly or indirectly, provides therotational movement to the gearing system 230 of the rotor (see FIG. 3),and any adapter 400 so capable is acceptable for use with the prophyangle 100. The adaptor 400 includes a body 410 and a nose 412, and thenose 412 may be removably attachable to the body 410. Alternatively, thenose 412 may be integral with the body 410. The adapter 400 includes ashaft 418 that is connected to a drive shaft 350 via a coupler 435. Theadaptor 400 may also include a supply conduit 430 (see FIGS. 7A and 7B)that is releaseably connectable to the inlet 132 of the housing conduit128.

An outer portion of the nose 412 may be shaped to mate with the prophyangle 10. As is known in the art, many types of different types ofprophy angles 100 exist that have different mating profiles, and thepresent adaptor 400 is not limited as to a particular shape of the nose412 and as to a particular profile of prophy angle 100 with which thenose 412 can mate. However, in a current aspect of the adapter 400, thenose 412 is a configured as a doriot-style adapter. Depending upon thetype of prophy angle 100, other type of connections devices include, butare not limited to, latch type, 3-ball chuck, attachment ring, pushchuck, quick-connect collars, autochucks, E-type (i.e., ISO 3964), DIN13940, ISO 1797, U-type, NSK type, and Midwest type.

The shaft 418 is rotated by the drive source 450. As is known in theart, many different types of drive sources 450 exist and these differentdrive sources 450 have different configurations for coupling with arotating member, such as the shaft 418. In this regard, the presentadapter 400 is not limited as to drive source 450 for the adapter 400.For example, the drive source 450 may be connectable to the adapter 400.Alternatively, the drive source 450 may be integrated with the adapter400. Also, examples of drive sources 450 include electrically-driven andpneumatically-driven motors. A further discussion on adapters 400 andconnections between the shaft 418 and either the drive source 450 orbetween the shaft 418 and the drive shaft 350 (e.g., via the coupler435) is found in related U.S. application Ser. No. 11/682,927 filed onMay 7, 2007, incorporated herein by reference in its entirety.

As illustrated, the drive shaft 350 is a part of the adaptor 400.However, the drive shaft 350 is not limited in this manner. For example,the drive shaft 350 may be a portion of the prophy angle 100. In otheraspects, the drive shaft 350 is removably attachable to a collet withinthe adaptor 400. In so doing, the drive shaft 350 can be replaceableand/or cleaned.

The adaptor 400 may include a retention device 440 for maintaining aposition of the prophy angle 100 on the adaptor 400 and any retentiondevice 440 so capable is acceptable for use with the adaptor 400. Incertain aspects of the adaptor 400, however, the retention device 440 isa locking pin 442 that is positionable within an opening 142 (see FIGS.5A-5B) in the housing 110 of the prophy angle 100. The locking pin 442may be resiliently biased such that after the locking pin 442 isdepressed, to either allow the prophy angle 100 to be positioned overthe adapter 400 or to remove the prophy angle 100 from the adapter 400,the locking pin 442 returns to an extended position. Upon the lockingpin 442 being positioned within the opening 142, the locking pin 442prevents removal of the prophy angle 100 from the adaptor 400.

Referring to specifically to FIGS. 7A and 7B, a slidable sleeve 460 maybe positioned over the drive shaft 350. The slidable sleeve 460 movesfrom an extended position (FIG. 7A), which conceals the gear 352 of thedrive shaft 350, to an retracted position (FIG. 7B), which reveals thegear 352 of the drive shaft 350. The slidable sleeve 460 is not limitedin the manner in which the slidable sleeve 460 moves from the extendedposition to the retracted position and back again. However, in certainaspects, the slidable sleeve 460 engages a second shoulder 144 (seeFIGS. 5A-5B) of the housing 110 as the slidable sleeve 460 is insertedinto the housing 110, which causes the slidable sleeve 460 to retractrelative to the gear 352 of the drive shaft 350.

The slidable sleeve 460 may also be connected to a resilient member 464,such as a spring, which is compressed upon the slidable sleeve 460 isretracted. Upon the slidable sleeve 460 being removed from the housing110, the resilient member 464 biases the slidable sleeve 460 into theextended position. In this manner, upon the adapter 400 being completelyremoved from the housing 110, even unintentionally, the gear 352 of thedrive shaft 350 is not exposed.

Referring to FIG. 8, while attached to the adaptor 400, the drive shaft350 may be capable of being biased along a line substantially parallelto a longitudinal axis of the drive shaft 350. Although any technique ofenabling the drive shaft 350 to be biased is acceptable for use, similarto the slidable sleeve 460, the drive shaft 350 may be connected to asecond resilient member 468, such as a spring.

Upon being inserted into the housing 110, the drive shaft 350 engagesthe gearing system 230, which biases the drive shaft 350 towards theadaptor 400. The second resilient member 468, in turn, pushes backagainst the drive shaft 350, which ensures proper engagement of the gear352 of the drive shaft with the gear system 230 of the rotor 200. Theability of the drive shaft 350 to be biased along the line substantiallyparallel to the longitudinal axis of the drive shaft 350 gives the driveshaft 350 linear adjustability relative to the body 410 of the adaptor400, and this linear adjustability allows for variations in dimensionsin the housing 110, rotor 200, drive shaft 350 and/or adaptor 400.

1. A dental prophy angle, comprising: a housing; and a rotor, whereinthe housing defining a first bore and a second bore in communicationwith the first bore, the rotor is disposed within the second bore, therotor includes a gearing system, the rotor includes a lock having a lockchannel configured to receive a tip of a drive shaft, the housingincludes a lock receiver for receiving the lock, the lock receiverpermitting rotation of the lock within the lock receiver and restraininglinear movement of the lock in a direction substantially parallel to arotational axis of the rotor.
 2. The dental prophy angle of claim 1,wherein the rotor includes a rotor conduit having an inlet and anoutlet, the housing includes a housing conduit having an inlet and anoutlet, and the outlet of the housing conduit is connectable to theinlet of the rotor conduit.
 3. The dental prophy angel of claim 2,wherein the inlet of the housing conduit is configured to be connectedto an outlet of a supply conduit positioned on an adaptor.
 4. The dentalprophy angle of claim 1, wherein the lock includes a upper portion and alower portion, and the upper portion and the lower portion define thechannel.
 5. The dental prophy angle of claim 1, further comprising aseal positioned between the housing and the rotor.
 6. The dental prophyangle of clam 1, wherein the second bore is adapted to removably receivethe drive shaft.
 7. A dental adapter for a prophy angle, comprising anose; a body connected to the nose; a drive shaft extending from thenose; and a slidable sleeve extending over at least a portion of thedrive shaft, wherein the drive shaft includes a gear, in a retractedposition of the slidable sleeve, the gear being revealed, and in anextended position of the slidable sleeve, the slidable sleeve at leastpartially covers the gear.
 8. The adapter of claim 7, wherein the driveshaft is linear movable relative to the body along a line substantiallyparallel to a longitudinal axis of the drive shaft.
 9. The adapter ofclaim 8, further comprising a resilient member connected to the driveshaft for biasing the drive shaft along the line.
 10. The adapter ofclaim 7, wherein the drive shaft includes a tip extending from a distalend of the drive shaft, and the tip is adapted to engage a rotor of theprophy angle.
 11. The adapter of claim 10, wherein the tip engages alock channel of the rotor to prevent linear motion of the rotor in adirection towards the drive shaft.
 12. The adapter of claim 7, furthercomprising a supply conduit configured to be connected to an inlet of aconduit in the prophy angle.
 13. The adapter of claim 7, wherein theadapter includes a drive source connected to the drive shaft by acoupler.
 14. The adapter of claim 7, further comprising a retentiondevice for maintaining a position of the prophy angle on the adaptor.15. A dental tool, comprising: a prophy angle; and an adapter forreceiving and driving the prophy angle, wherein the prophy angleincludes a housing and a rotor, and the adapter includes a body, a driveshaft for driving the rotor, a slidable sleeve, and a nose for receivingthe prophy angle.
 16. The dental tool of claim 15, wherein the rotorincludes a lock having a lock channel configured to receive a tip of adrive shaft, the engagement of the lock channel and the tip restrainingmovement of the rotor lock in a direction towards the drive shaft andrestraining movement of the lock relative to the tip in a directionsubstantially parallel to a rotational axis of the rotor.
 17. The dentaltool of claim 16, wherein in a retracted position of the slidablesleeve, a gear of the drive shaft is revealed, and in an extendedposition of the slidable sleeve, the slidable sleeve at least partiallycovers the gear.
 18. The dental tool of claim 16, wherein the driveshaft is linear movable relative to the body along a line substantiallyparallel to a longitudinal axis of the drive shaft.
 19. The dental toolof claim 16, wherein the rotor includes a lock, the housing includes alock receiver for receiving the lock, the lock receiver permittingrotation of the lock within the lock receiver and restraining linearmovement of the lock in a direction substantially parallel to arotational axis of the rotor.
 20. The dental tool of claim 16, whereinthe rotor includes a rotor conduit having an inlet and an outlet, thehousing includes a housing conduit having an inlet and an outlet, theadapter includes a supply conduit having an outlet, the outlet of thehousing conduit is connected to the inlet of the rotor conduit, and theoutlet of the supply conduit is releaseably connected to the inlet ofthe housing conduit.
 21. A dental tool, comprising: a prophy anglecomprising a housing and a rotor; and, a prophy angle adapter configuredto receive the prophy angle, the prophy angle adapter comprising: adrive shaft comprising a tip at a distal end of the drive shaft and agear proximal to the tip on the drive shaft, wherein the rotor isconfigured to receive the tip, a slidable sleeve extending over at leasta portion of the drive shaft, wherein the slidable sleeve becomesautomatically retracted upon engaging a shoulder of the housingresulting in the gear of the drive shaft being revealed.
 22. The adapterof claim 21, further comprising a resilient member connected to theslidably sleeve.
 23. The adapter of claim 22, wherein the resilientmember is a spring.
 24. A method for revealing a gear in a prophy angleadapter, comprising the steps of: inserting a slidable sleeve positionedat least partially over a drive shaft of a prophy angle adapter into ahousing of a prophy angle; engaging a shoulder of the housing of theprophy angle; and, retracting automatically the slidable sleeve toreveal a gear coupled to the drive shaft upon engaging the shoulder ofthe housing.
 25. A method for revealing a gear in a prophy angleadapter, comprising the steps of: connecting a slidable sleeve to aspring of a prophy angle adapter; retracting the slidable sleeve uponcompressing the spring to reveal a gear coupled to a drive shaft of theprophy angle adapter; and, biasing the slidable sleeve into an extendedposition resulting in the gear not being exposed upon removing theslidable sleeve from a housing of a prophy angle.